The only thing I think would be better about this is if we had some way of showing pre-reqs.

Now: For questions, for damage dealers, what is the actual value of taking Butcher? It seems like the attack speed/cooldown are almost always better, and then the later tiers never feel like you have empty points (unlike in utility where, sometimes, I feel like it is OK to backfill lower tiers.)

I always take 2/2 butcher and only take 1/3 havoc. It improves last hitting a bit, which is something I definitely need the help with. If in the first 20 minutes you get an extra 10 cs it's worth about 250 gold. It's completely personal preference though.

Personally, I feel like not enough people take Butcher. It's common to see people go 1/0/3/0 in the first tier for mages/tanks/champions that revolve around CDR, but I feel as though 1/0/1/2 or 0/0/2/2 for Igniteless champions is much stronger because 2% CDR won't affect you much (especially if you itemize for CDR) whereas an additional 4 damage on your autos can get you a lot of potential CS that you would not be able to get normally. It also helps you clear jungle monsters faster, especially if you're a midlaner.

The most common mistake people make is to take points in Havoc. If you study Korean rune pages, you will notice that veryfew of them take any points in Havoc, and almost all of them take points in Butcher, Sorcery, and Destruction instead. On ADCs in particular, Destruction is much more valuable than 0.67% increased damage.